ABSTRACT
By analyzing the fine structure of varicella-zoster virus (VZV) DNA, a naturally occurring heterogeneity was found on the right end of VZV DNA, but no evidence of a true terminal repetition was uncovered. We were unable to confirm the report of Straus and co-workers (1981) that there is a relatively high frequency of circular VZV DNA in low-passage virus. On long-term cell passage, extensive heterogeneity appeared concomitant with the accumulation of apparently defective VZV DNA.
Subject(s)
DNA, Viral/genetics , Herpesvirus 3, Human/genetics , Chromosome Mapping , DNA Restriction Enzymes , DNA, Circular/genetics , Polymorphism, Genetic , Repetitive Sequences, Nucleic AcidABSTRACT
To isolate stable recombinants containing the 'joint region', or L-S junction, of herpes simplex virus DNA, the EcoRI restriction enzyme cleavage fragments were cloned into both coliphage lambda and plasmid vectors. The authentic joint region was found in the plasmid but not in the lambda vector. The plasmid-joint region recombinant DNAs appeared stable on limited passage. Subcloning the small BamHI L-S junction fragment into plasmid pBR322 gave rise to both stable and unstable recombinant DNAs.
Subject(s)
Cloning, Molecular , DNA, Viral/genetics , Simplexvirus/genetics , Bacteriophage lambda/genetics , Base Sequence , DNA Restriction Enzymes , DNA, Recombinant , Deoxyribonuclease EcoRI , Plasmids , Repetitive Sequences, Nucleic AcidABSTRACT
The DNAs of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) were separately denatured and allowed to renature briefly. The intrastand foldback structures that resulted from base pairing of inverted repeated sequences on otherwise single-stranded (ss) DNA were visualized in the electron microscope. The two genomes were found to contain similar size classes of small duplex stem DNA sequences. However, HSV-2 DNA appeared to possess an additional, larger size class of foldback structures not found on HSV-1 DNA. Both HSV DNAs were found to contain stem-plus-loop structures; the larger stem-plus-loop structures of the two genomes had similar stem lengths but dissimilar loop lengths. Thus, a comparison of the genomes of HSV-1 and HSV-2 showed that they possessed similar size classes of foldback sequences.
